j query resizable is not working

j query resizable is not working

hi
this is my small code just coppyed from demo and a little changed
but i can't resize the div
all the file are present in the same directory
<html>
<head>
<script language="JavaScript" src="jquery-1.3.2.js"></script>
<script language="JavaScript" src="ui.core.js"></script>
<script language="JavaScript" src="ui.resizable.js"></script>
<link type="text/css" href="ui.all.css" rel="stylesheet" />
<link type="text/css" href="demos.css" rel="stylesheet" />
<style type="text/css">
    #resizable { width: 150px; height: 150px; padding: 0.5em; }
    #resizable h3 { text-align: center; margin: 0; }
    </style>
    <script type="text/javascript">
    $(function() {
        $("#resizable").resizable();
        alert('ayan');
    });
    </script>
</head>
<body>
<div class="demo">
<div id="resizable" class="ui-widget-content">
    <h3 class="ui-widget-header">Resizable</h3>
</div>
</div><!-- End demo -->
<div class="demo-description">

Enable any DOM element to be resizable. With the cursor grab the
right or bottom border and drag to the desired width or height.


</div><!-- End demo-description -->
</body>
</html>
thanks
ayan
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